In conventional travelling-wire electroerosion machines, wire-electrode feed assemblies are commonly utilized having a configuration such that the wire electrode fed from a supply reel, which is provided on the machine column or on the frontal wall of the machine, is advanced through one of two arms attached to the machine column or is otherwise fed along the frontal wall to reach the vicinity of an end thereof, wherefrom the wire under tension is advanced via the other arm for take-up by a take-up reel which is also provided on the machine column.
Electroerosion machines with such travelling electrode assemblies lack flexibility or versatility in that they do not lend themselves to a certain kinds of important applications. For example, they are not amenable to counter-machining of the head portion of an I-shaped member as encountered, for example, in machining of a hollow portion of an extrusion die and an edge portion of a trimming die, and are thus quite inconvenient.